4）油泵主動(dòng)齒輪油封損壞，空氣進(jìn)入液壓系統(tǒng)；排除方法：更換老化的或損壞的油封、O形密封圈單向順序閥HGP-1A-L1L單向順序閥
單向順序閥HGP-1A-L1L①軸頸不適宜，使油封唇口部位磨損，發(fā)熱——排除方法：檢查尺寸，換軸。油封處的公差常用h8YB1-20/12,YB1-16/16,YB1-12/12,YB1-50/10,YB1-50/6,YB1-50/4,YB1-50/2.5,YB1-40/10,YB1-40/6,YB1-40/4,YB1-40/2.5,YB1-32/10,YB1-32/6,YB1-32/4,YB1-50/25,YB1-50/20,YB1-50/16,YB1-50/12,YB1-40/25,YB1-40/20,YB1-40/16,YB1-40/12,YB1-32/25,YB1-32/20,YB1-32/16,YB1-50/50,YB1-50/40,YB1-50/32,YB1-40/40,YB1-40/32,YB1-32/32,YB1-100/10,YB1-100/6,YB1-100/4,YB1-100/2.5,YB1-80/10,YB1-80/6,YB1-80/4,YB1-80/2.5,YB1-63/10,YB1-63/6,YB1-63/4,YB1-63/2.5,YB1-100/25,YB1-100/20,YB1-100/16,YB1-100/12,YB1-80/25,YB1-80/20,YB1-80/16,YB1-80/12,YB1-63/25,YB1-63/20,YB1-63/16,YB1-63/12,YB1-100/50,YB1-100/40,YB1-100/32,YB1-80/50,YB1-80/40,YB1-80/32,YB1-63/50,YB1-63/40,YB1-63/32,YB1-100/100,YB1-100/80,YB1-100/63,YB1-80/80,YB1-80/63,YB1-63/63.
YB-D50 YB-D63 YB-D80 YB-D1003、油液粘度過(guò)大，危害性大，發(fā)生率較高：油的粘度過(guò)大，主要是過(guò)度使用所造成的，而一旦出現(xiàn)，就會(huì)使吸油困難，會(huì)使局部產(chǎn)生真空現(xiàn)象，使原來(lái)溶解在油內(nèi)的空氣分離出來(lái)，這些空氣使設(shè)備工作產(chǎn)生很大的震動(dòng)，使機(jī)器的部件過(guò)早的損壞。油的粘度過(guò)大，會(huì)使濾芯早早的失效，并使機(jī)器的油泵受到損傷。單向順序閥HGP-1A-L1L
